How do you find the center of dilation for a negetive dilation?

An ulcer medication has 300 milligrams in 2 tablets. how many milligrams are in 3 tablets?

Aline passes through 3,7 and 6,9 what equation represents the line

An investment decreases in value by 30% in the first year and decreases by 40% in the second year. what is the percent decrease in percentage in the investment after two years